As computer systems continue to become smaller and have lower profiles (i.e., a smaller physical size), generation of airflow and pressure necessary to cool electronics contained therein becomes more difficult. Conventional blower fans have been used to cool computer electronics. Blower fans traditionally develop dynamic pressure via an increase in angular speed of their spinning blade array. This dynamic pressure is then converted to static pressure in a diffusion section outside a rotating or spinning wheel that is coupled to the array in a volute or involute.
When a blower fan is placed in a low profile system, where air cannot enter an intake to the blower fan in the same direction of the axis of rotation of the blower fan, a pressure drop may impede the intake and thus may reduce the blower fan's effectiveness. Current blower fan designs combat increases in intake impedance by increasing the blower fan speed, which may increase acoustic noise associated with the blower fan.
Some manufacturers have employed axial fans to cool computer electronics. However, axial fans fail to generate adequate airflow and pressure for prolonged cooling, particularly when sandwiched between circuit board cards that axially constrain airflow at an inlet and an outlet of the axial fan.